Last update : 12/1/2004

wcenter - center and weight

### Calling Sequence

  `s=wcenter(x)`
  `s=wcenter(x,'r') or s=wcenter(x,1)`
  `s=wcenter(x,'c') or s=wcenter(x,2)`

### Parameters

- ``x: real or complex vector or matrix

### Description

This function computes `s`, the weigthed and centred version of the numerical matrix `x`.

For a vector or a matrix `x`, `s=wcenter(x)` returns in the `(i,j)` coefficient of the matrix `s` the value `(x(i,j)-xbar)/sigma`, where `xbar` is the mean of the values of the coefficients of `x` and `sigma` his standard deviation.

`s=wcenter(x,'r')` (or, equivalently, `s=wcenter(x,1)`) is the rowwise centre reduction of the values of `x`. It returns in the entry `s(i,j)` the value `(x(i,j)-xbarv(j))/sigmav(j)` with `xbarv(j)` the mean of the values of the `j` column and `sigmav(j)` the standard deviation of the `j` column of `x`.

`s=wcenter(x,'c')` (or, equivalently, `s=wcenter(x,2)`) is the columnwise centre reduction of the values of `x`. It returns in the entry `s(i,j)` the value `(x(i,j)-xbarh(i))/sigmah(i)` with `xbarh(i)` the mean of the values of the `i` row and `sigmah(i)` the standard deviation of the `i` row of `x`.

### Examples

    x=[0.2113249 0.0002211 0.6653811;
       0.7560439 0.3303271 0.6283918]
    s=wcenter(x)
    s=wcenter(x,'r')
    s=wcenter(x,'c')

### See Also

`center`,

### Author

Carlos Klimann